With improvements in battery design, many battery-powered devices require that a relatively large amount of electrical current be carried when operating the battery-powered device. It is also common that this electrical current must be carried through an electrical connector so that a more fully charged battery can be easily plugged into the battery-powered device or that other control cables must be easily connected or disconnected. Because of the large amount of current flowing in such battery-powered devices, some electrical connectors have a risk of galling at the interface between a male and female connector which in turn would cause an increased electrical resistance. The increased electrical resistance can lead to a heating and often destruction of the electrical connector or reduced performance of the battery powered device.
An example of an electrical connector assembly capable of carrying a large amount of current is disclosed by Deans, U.S. Pat. No. 5,533,915 (“the '915 patent”). The '915 patent generally describes a male connector assembly 10 and a female connector assembly 11. A male connector pin 12 of the male connector assembly has a top 16, a bottom 17, a first side 18, a second side 19, a forward end 20, and a rearward end 21 and is fabricated from copper which has preferably been nickel plated followed by gold plating. A leaf spring 14 has a flat length 27 held within connector body 25 and a curved length 26 that extends past a face 28 of the connector body 25. Male conductors 42 and 43 are soldered near the rearward end 21 of each of the connector pins in a manner analogous to that shown on the female connector assembly 11.
The '915 patent also describes a female connector body 45 having a first side 46, a second side 47, a top 48, a bottom 49 and a back 50 and also a generally rectangular upper opening 51 and a lower generally rectangular opening 52 identical to 51 except that it is rotated 270 degrees as viewed in FIG. 7. Female connector pin 59 can be seen to have a top 60, a bottom 61, a forward end 62, a rearward end 63, a first side 64, and a second side 65. Connector pin 59 is shown in phantom view in FIG. 8 where it can be seen that the forward end 62 is recessed from the face 44. This helps to avoid any undesired contact of male connector pins 12 and 13 unless they are oriented properly so that they will pass beneath the face 44 of connector body 45. It can also be fairly seen in FIG. 1 that conductor 68 is soldered at 69 to a rearward portion of female connector pin 59 which extends past back 50 of conductor body 45. Similarly, conductor 70 is soldered at 71 to connector pin 59′. The connector pins 12, 13, 59, and 60 are connectable externally to the electrical connector assembly at their respective rearward portions. The connector pins 12, 13, 59, and 60 thus provide an external connection to the battery and/or battery-powered device via the conductors 42, 43, 68, and 70. In other words, the battery and battery-powered device are electrically connected via the conductors 42 and 43, the male connector pins 12 and 13, the female connector pins 59 and 60, and the conductors 68 and 70.
In operation of the connector assembly of the '915 patent, connector pins 12 and 13 are inserted into generally rectangular openings 51 and 52. The leaf spring 14 contacts the top 53 of rectangular opening 52, thereby forcing the leaf spring 14 of connector pin 12 against the top 60 of connector pin 59. This provides an effective contact area and yet the male and female connectors do not require excessive force to be plugged together or to be unplugged. The connector bodies are preferably fabricated from strong dielectric materials such as glass fiber reinforced nylon. The '915 patent indicates that when using a gold plated male connector and a silver plated female connector, it has been found that the resulting connection is capable of passing 30 amps from an 8 volt battery without any breakdown at the connection.
Although the electrical connector assembly described in the '915 patent helps to avoid undesired contact of male connector pins 12 and 13, it does not provide protection or shielding to reduce breakdown at the rearward ends of the male connector pins 12, 13 or the rearward ends of the female connector pins 59 and 60. As shown in FIG. 1 of the '915 patent, the conductor 68 is soldered at 69 to the portion of female connector pin 59. The configuration of the '915 patent relies upon a sufficient air separation between soldering joints for the conductor 68 and conductor 70. The size of the air separation is affected by the quality of the soldering joints, which may be performed by a non-professional hobbyist, for example, in the case that the battery-powered device is a remote controlled (RC) car, airplane, helicopter, boat, or other suitable RC device.
Additionally, the electrical connector assembly described in the '915 patent does not protect or shield the rearward ends of the connector pins 12, 13, 59, and 60 from a short-circuit that may be caused by contact with a foreign object. For example, a battery placed in a container with metallic spare parts, keys, or other suitably conductive objects may short-circuit if the air separation between the conductors is effectively reduced by contact with a conductive object.
Another example of an electrical connector assembly is disclosed by Hariharesan et al., U.S. Pat. No. 7,374,460 (“the '460 patent”). The '460 patent generally describes an electrical connector 1000 having a male member 500 with male terminals 600 and a female member 100 with female terminals 200. Retention members 512 are configured to retain the male terminal 600 after assembly into the male member 500. As shown in FIG. 6A of the '460 patent, the male terminals 600 are shielded from each other by the housing 502, thus providing protection from breakdown between the male terminals 600, but the unitary housing and retention members 512 reduce accessibility of the male terminals 600. While the male terminal 600 can be soldered to a conductor before insertion into the male member 500, the retention members 512 impede removal of the male terminal 600 or disconnection of a connected conductor, for example, to perform maintenance, cleaning, or removal of the electrical connector assembly for installation on a different battery or battery-powered device.